(a) Field of the Invention
The present invention relates to a mobile communication, and in particular, to a method and system for multicasting and broadcasting IP (Internet Protocol) data in mobile communication system, and a terminal thereof.
(b) Description of the Related Art
IMT-2000 supports voice and data communication using wireless packet switching and global roaming services as well as conventional circuit switching. With the IMT-2000 recommendations is complete the 3G (third generation) standardization processes are coming to closure by the 3GPP (Third Generation Partnership Project) concentrated on the DS-WCDMA (UMTS: Universal Mobile Telecommunications Systems) technology and the 3GPP2 based on the MC-WCDMA (CDMA 2000) technology. There has been much researches and studies on 3G mobile communication network and data transmission technologies such as WCDMA in wireless network and GPRS/mobile IP in the core network etc. for providing stable packet data service with enhanced QoS for voice and data transmission.
FIG. 1 is a schematic view showing a present mobile communication network for IP packet data service.
As shown in FIG. 1, the conventional mobile communication network includes servers 102 and router 104 as parts of the Internet; a carrier intranet having a Home Agent (HA) 108 working as a gateway for mobile IP users accessing to the Internet, an AAA (Authentication, Authorization, and Accounting) server 110 for authenticating, authorizing, and accounting the users; packet data serving nodes (PDSN) 202 for providing interface between a Radio Access Network (RAN) 200 and DCN; Base Station Controller (BCN) providing PPP link for data transmission and managing resources; Packet Control Function (PCF) 204 for packet access service; Base Transmission Station (BTS) 206 for call processing of mobile stations; mobile stations 208 for receiving broadcasting messages from the base station through the PPP links; and Mobile Service Switching Center (MSC)/Visitor Location Register (VLR) 112.
The operation of the packet data access service in the above structured mobile communication network will be described hereinafter.
The mobile communication network is coupled to the Internet 100 and includes PDSN1 and PDSN2 202 for providing the packet data service, the MSC/VLR 112 for providing outer network access service, the base station system (BSS), and the mobile stations 208, the BSS including the BSCs/PCF 204 for controlling Radio resources and the BTS 206.
The MSC/VLR 112 controls mobility of the mobile stations 208, connection call, radio resource allocation, wired network connection through the BSS and communicates the PSTN/PCS/PLMN networks 116 and the HLR/AUC.
The PSDN 202 provides interface functions between the RAN 200 and DCN. That is, the PSDN 202 is a data link layer termination point and performs routing with higher layer protocols.
The PSDN 202 multicasts (transmits same packets to specific nodes at the same subnets) or broadcasts (transmits the same packets to all the nodes) packets to the mobile stations.
In this mobile communication network, a mobile computing device such as a notebook and wireless data communication supportable mobile communication terminal are required for the Internet packet data access service. The mobile computing device and the mobile communication terminal are connected using a cable through serial ports provided at the devices. After the physical connection, wireless data communication can be performed only by installing communication application and setting for connection establishment.
The mobile station 208 is wirelessly connected to the BTS 206 for packet service such that the BTS 206 establishes radio link between the BSC/PCFs and is connected to the PDSN 202. Accordingly, a PPP (Point to Point Protocol) link is established between the mobile station 208 and the PDSN 202.
In this case, the IP packet data from the server 102 and router 104 as parts of the Internet 100 are transmitted to the carrier intranet 106, and the carrier intranet 106 functions takes roles for providing the gateway for the mobile IP users and authenticating, authorizing, and accounting the users, with the HA 108 and AAA server 110.
The PDSNs 202 receives multicasting/broadcasting IP datagrams or messages from the Internet 100 and transmits the IP datagrams to the corresponding mobile stations through the PPP links established there between.
The mobile station 208 receives the IP datagrams through the established PPP link.
In more detail, the mobile station 208 separately establishes PPP links with base station-base station controller/packet controller-packet data serving node so as to receive multicasting/broadcasting IP datagrams or messages through the PDSN 202.
In this case, a plurality of PPP channels for respective mobile stations 208 are assigned so as to communicate the PDSN 202 such that much resources are required for multicasting/broadcasting the same messages.
When the multicasting data received from the Internet is broadcasted to all the mobile stations or multicasted to a specific group of mobile stations, the corresponding mobile stations occupy traffic channels. In view of the mobile communication network, since the radio channels are shared by all the mobile stations, this is not the multicasting but respective channel occupancies. This causes radio resources waste and the resources required for the wired BTS-BSC/PCF-PDSN connections are used in proportional with the number of the connected mobile stations, resulting in inefficient multicasting message transmission.